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Re: XML format for Higher Order meshes

 

I will try this.

- Shawn

On Tue, 26 Aug 2008, Anders Logg wrote:

On Mon, Aug 25, 2008 at 06:14:49PM -0400, Shawn Walker wrote:
So, would this function be read into a variable inside the MeshGeometry
class?  if so, then I will try to modify the XMLMesh file to account for
reading a <coordinates> tag.  Although I am still a little confused on
how the proposed <dofmap> tag in <function> works.

- Shawn

Yes, I'd suggest that we add a (private) member variable

 Function* coordinates;

to the MeshGeometry class and rename the current array
coordinates to vertex_coordinates.

It should be set to zero if there are no higher order coordinates
available.

--
Anders


On Mon, 25 Aug 2008, Anders Logg wrote:

2. It also makes an assumption about the numbering of degrees of
freedom (and mesh entities) always being the same. This can be handled
by adding a new tag <dofmap> under <function> that contains the dofs
explicitly (not the signature of the FFC dof map).

The XML format could be something like

 <mesh celltype="triangle" dim="2">
   <vertices size="2868">
     <vertex index="0" x="0.534923" y="0.326073"/>
     ...
   </vertices>
   <cells size="5400">
     <triangle index="0" v0="76" v1="914" v2="1153"/>
     ...
   </cells>
   <coordinates>
     <function>

     </function>
   </coordinates>
 <mesh

ok, I guess you would need to add an attribute to the `function' to
specify what kind of finite element it is.  You could also add a boolean
function to the <coordinates> section that would indicate whether the
element is indeed curved or not.

Yes, we could do something like

<coordinates degree="2">

and then have the boolean affine="true"/"false" inside the cell tags.



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